2022-09-13 08:35:45

by Chao Yu

Subject: [PATCH v3] f2fs: fix to detect corrupted meta ino

It is possible that ino of dirent or orphan inode is corrupted in a
fuzzed image, occasionally, if corrupted ino is equal to meta ino:
meta_ino, node_ino or compress_ino, caller of f2fs_iget() from below
call paths will get meta inode directly, it's not allowed, let's
add sanity check to detect such cases.

case #1
- recover_dentry
- __f2fs_find_entry
- f2fs_iget_retry

case #2
- recover_orphan_inode
- f2fs_iget_retry

Signed-off-by: Chao Yu <[email protected]>
---
v3:
- update commit title/message
- change logic inside f2fs_iget() rather than its caller
fs/f2fs/inode.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index cde0a3dc80c3..1baac6056733 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -487,6 +487,12 @@ static int do_read_inode(struct inode *inode)
return 0;
}

+static bool is_meta_ino(struct f2fs_sb_info *sbi, unsigned int ino)
+{
+ return ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) ||
+ ino == F2FS_COMPRESS_INO(sbi);
+}
+
struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
@@ -497,17 +503,22 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
if (!inode)
return ERR_PTR(-ENOMEM);

+ if (is_meta_ino(sbi, ino)) {
+ if (!(inode->i_state & I_NEW)) {
+ f2fs_err(sbi, "detect corrupted inode no:%lu, run fsck to repair", ino);
+ set_sbi_flag(sbi, SBI_NEED_FSCK);
+ ret = -EFSCORRUPTED;
+ trace_f2fs_iget_exit(inode, ret);
+ iput(inode);
+ return ERR_PTR(ret);
+ }
+ goto make_now;
+ }
+
if (!(inode->i_state & I_NEW)) {
trace_f2fs_iget(inode);
return inode;
}
- if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
- goto make_now;
-
-#ifdef CONFIG_F2FS_FS_COMPRESSION
- if (ino == F2FS_COMPRESS_INO(sbi))
- goto make_now;
-#endif

ret = do_read_inode(inode);
if (ret)
--
2.25.1

2022-09-22 02:37:23

by Chao Yu

Subject: Re: [PATCH v3] f2fs: fix to detect corrupted meta ino

Ping,

On 2022/9/13 15:48, Chao Yu wrote:
> It is possible that ino of dirent or orphan inode is corrupted in a
> fuzzed image, occasionally, if corrupted ino is equal to meta ino:
> meta_ino, node_ino or compress_ino, caller of f2fs_iget() from below
> call paths will get meta inode directly, it's not allowed, let's
> add sanity check to detect such cases.
>
> case #1
> - recover_dentry
> - __f2fs_find_entry
> - f2fs_iget_retry
>
> case #2
> - recover_orphan_inode
> - f2fs_iget_retry
>
> Signed-off-by: Chao Yu <[email protected]>
> ---
> v3:
> - update commit title/message
> - change logic inside f2fs_iget() rather than its caller
> fs/f2fs/inode.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> index cde0a3dc80c3..1baac6056733 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -487,6 +487,12 @@ static int do_read_inode(struct inode *inode)
> return 0;
> }
>
> +static bool is_meta_ino(struct f2fs_sb_info *sbi, unsigned int ino)
> +{
> + return ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) ||
> + ino == F2FS_COMPRESS_INO(sbi);
> +}
> +
> struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
> {
> struct f2fs_sb_info *sbi = F2FS_SB(sb);
> @@ -497,17 +503,22 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
> if (!inode)
> return ERR_PTR(-ENOMEM);
>
> + if (is_meta_ino(sbi, ino)) {
> + if (!(inode->i_state & I_NEW)) {
> + f2fs_err(sbi, "detect corrupted inode no:%lu, run fsck to repair", ino);
> + set_sbi_flag(sbi, SBI_NEED_FSCK);
> + ret = -EFSCORRUPTED;
> + trace_f2fs_iget_exit(inode, ret);
> + iput(inode);
> + return ERR_PTR(ret);
> + }
> + goto make_now;
> + }
> +
> if (!(inode->i_state & I_NEW)) {
> trace_f2fs_iget(inode);
> return inode;
> }
> - if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
> - goto make_now;
> -
> -#ifdef CONFIG_F2FS_FS_COMPRESSION
> - if (ino == F2FS_COMPRESS_INO(sbi))
> - goto make_now;
> -#endif
>
> ret = do_read_inode(inode);
> if (ret)

2022-09-22 18:16:54

by Jaegeuk Kim

Subject: Re: [PATCH v3] f2fs: fix to detect corrupted meta ino

I modified a bit.

https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev-test&id=a9a1592fa175baaaae43f54f175a972757c47919

Thanks,

On 09/22, Chao Yu wrote:
> Ping,
>
> On 2022/9/13 15:48, Chao Yu wrote:
> > It is possible that ino of dirent or orphan inode is corrupted in a
> > fuzzed image, occasionally, if corrupted ino is equal to meta ino:
> > meta_ino, node_ino or compress_ino, caller of f2fs_iget() from below
> > call paths will get meta inode directly, it's not allowed, let's
> > add sanity check to detect such cases.
> >
> > case #1
> > - recover_dentry
> > - __f2fs_find_entry
> > - f2fs_iget_retry
> >
> > case #2
> > - recover_orphan_inode
> > - f2fs_iget_retry
> >
> > Signed-off-by: Chao Yu <[email protected]>
> > ---
> > v3:
> > - update commit title/message
> > - change logic inside f2fs_iget() rather than its caller
> > fs/f2fs/inode.c | 25 ++++++++++++++++++-------
> > 1 file changed, 18 insertions(+), 7 deletions(-)
> >
> > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> > index cde0a3dc80c3..1baac6056733 100644
> > --- a/fs/f2fs/inode.c
> > +++ b/fs/f2fs/inode.c
> > @@ -487,6 +487,12 @@ static int do_read_inode(struct inode *inode)
> > return 0;
> > }
> > +static bool is_meta_ino(struct f2fs_sb_info *sbi, unsigned int ino)
> > +{
> > + return ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) ||
> > + ino == F2FS_COMPRESS_INO(sbi);
> > +}
> > +
> > struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
> > {
> > struct f2fs_sb_info *sbi = F2FS_SB(sb);
> > @@ -497,17 +503,22 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
> > if (!inode)
> > return ERR_PTR(-ENOMEM);
> > + if (is_meta_ino(sbi, ino)) {
> > + if (!(inode->i_state & I_NEW)) {
> > + f2fs_err(sbi, "detect corrupted inode no:%lu, run fsck to repair", ino);
> > + set_sbi_flag(sbi, SBI_NEED_FSCK);
> > + ret = -EFSCORRUPTED;
> > + trace_f2fs_iget_exit(inode, ret);
> > + iput(inode);
> > + return ERR_PTR(ret);
> > + }
> > + goto make_now;
> > + }
> > +
> > if (!(inode->i_state & I_NEW)) {
> > trace_f2fs_iget(inode);
> > return inode;
> > }
> > - if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
> > - goto make_now;
> > -
> > -#ifdef CONFIG_F2FS_FS_COMPRESSION
> > - if (ino == F2FS_COMPRESS_INO(sbi))
> > - goto make_now;
> > -#endif
> > ret = do_read_inode(inode);
> > if (ret)

2022-09-25 14:31:05

by Chao Yu

Subject: Re: [PATCH v3] f2fs: fix to detect corrupted meta ino

On 2022/9/23 2:11, Jaegeuk Kim wrote:
> I modified a bit.
>
> https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev-test&id=a9a1592fa175baaaae43f54f175a972757c47919

Fine to me. :)

Thanks,

>
> Thanks,
>
> On 09/22, Chao Yu wrote:
>> Ping,
>>
>> On 2022/9/13 15:48, Chao Yu wrote:
>>> It is possible that ino of dirent or orphan inode is corrupted in a
>>> fuzzed image, occasionally, if corrupted ino is equal to meta ino:
>>> meta_ino, node_ino or compress_ino, caller of f2fs_iget() from below
>>> call paths will get meta inode directly, it's not allowed, let's
>>> add sanity check to detect such cases.
>>>
>>> case #1
>>> - recover_dentry
>>> - __f2fs_find_entry
>>> - f2fs_iget_retry
>>>
>>> case #2
>>> - recover_orphan_inode
>>> - f2fs_iget_retry
>>>
>>> Signed-off-by: Chao Yu <[email protected]>
>>> ---
>>> v3:
>>> - update commit title/message
>>> - change logic inside f2fs_iget() rather than its caller
>>> fs/f2fs/inode.c | 25 ++++++++++++++++++-------
>>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
>>> index cde0a3dc80c3..1baac6056733 100644
>>> --- a/fs/f2fs/inode.c
>>> +++ b/fs/f2fs/inode.c
>>> @@ -487,6 +487,12 @@ static int do_read_inode(struct inode *inode)
>>> return 0;
>>> }
>>> +static bool is_meta_ino(struct f2fs_sb_info *sbi, unsigned int ino)
>>> +{
>>> + return ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) ||
>>> + ino == F2FS_COMPRESS_INO(sbi);
>>> +}
>>> +
>>> struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
>>> {
>>> struct f2fs_sb_info *sbi = F2FS_SB(sb);
>>> @@ -497,17 +503,22 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
>>> if (!inode)
>>> return ERR_PTR(-ENOMEM);
>>> + if (is_meta_ino(sbi, ino)) {
>>> + if (!(inode->i_state & I_NEW)) {
>>> + f2fs_err(sbi, "detect corrupted inode no:%lu, run fsck to repair", ino);
>>> + set_sbi_flag(sbi, SBI_NEED_FSCK);
>>> + ret = -EFSCORRUPTED;
>>> + trace_f2fs_iget_exit(inode, ret);
>>> + iput(inode);
>>> + return ERR_PTR(ret);
>>> + }
>>> + goto make_now;
>>> + }
>>> +
>>> if (!(inode->i_state & I_NEW)) {
>>> trace_f2fs_iget(inode);
>>> return inode;
>>> }
>>> - if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
>>> - goto make_now;
>>> -
>>> -#ifdef CONFIG_F2FS_FS_COMPRESSION
>>> - if (ino == F2FS_COMPRESS_INO(sbi))
>>> - goto make_now;
>>> -#endif
>>> ret = do_read_inode(inode);
>>> if (ret)